Carton forming apparatus



Nov. 5, 1968 F. L. HOF'F 3,408,905

CARTON FORMING APPARATUS Filed April 11, 1966 3 Sheets-Sheet l e2 44 2354 ii IO 4a l 69 48 5G 19 w as Z1 F I G' 1 INVEN'I'OR FRANCIS L. HOFFATTORNEY Nov. 5, 1938 HOFF 3,408,905

CARTON FORMING APPARATUS FilQd April 11, i966 5 Sheets-Sheet 2 INVENTORFRANCIS L. HOFF ATTORNEY Nov. 5, 1968 F. L. HOFF 3,408,905

CARTON FORMING APPARATUS Filed April 11, 1966 a Sheets-Sheet s 52. F EEHI H2 INVENTOR FRANCIS L. HOFF A'ITORNEY United States 3,408,905 CARTONFORMING APPARATUS Francis L. Hofi, Santa Clara, Calif., assignor to FMCCorporation, San Jose, Calif., a corporation of Delaware Filed Apr. 11,1966, Ser. No. 541,813 3 Claims. (Cl. 93-368) ABSTRACT OF THE DISCLOSUREThe present invention pertains to packaging machines, and moreparticularly relates to a flap folding apparatus for bending fiaps aboutscore lines.

In carton forming and filling machines of the type disclosed in thecopending application for United States Letters Patent of Vades et al.,Ser. No. 461,738, filed June 7, 1965, a top forming turret is disclosed.The top forming turret turret is arranged to first insert a backup anvilinto a carton opposite score lines therein and thereafter lower aforming head having rigid flap folding members into folding position sothat the rigid members engage the four top closure flaps of the cartonand bend them inwardly about the associated score lines. In order toprovide a scalable carton, it is essential that two opposed flaps havingtrapezoidal score lines therein be folded inwardly before the other twoopposed flat flaps can be bent inwardly.

It has been discovered that if the cartons presented to the forming headare improperly positioned in their carriers and accordingly are notaccurately aligned with the forming head, one of the fixed foldingmembers of each forming head is apt to contact one of the front flaps ofan associated misaligned carton before the trapezoidal flaps arecontacted and bent inwardly thereby causing the trapezoidal flaps to bebent outwardly, rather than inwardly, providing a defective carton.

In order to overcome the above difficulty and to provide a formingapparatus which will operate successfully on cartons even though theyare misaligned, it is one object of the present invention to provide animproved carton forming apparatus.

Another object is to provide a carton forming apparatus having a forminghead provided with a pair of folding members which are held away fromthe flat flaps of a carton until after the trapezoidal flaps have beenengaged and have been bent inwardly.

Another object is to provide an improved carton forming head.

These and other objects and advantages of the present invention willbecome apparent from the following description and the accompanyingdrawings, in which:

FIGURE 1 is a vertical central section through the carton formingapparatus of the present invention, only two forming assemblies beingillustrated.

FIGURES 2, 3 and 4 are enlarged vertical sections through one of theforming head assemblies illustrating the forming head and anvil in threeoperative positions.

FIGURE 5 is an enlarged horizontal section taken along lines 55 ofFIGURE 2.

FIGURE 6 is an enlarged vertical section taken substantially along lines66 of FIGURE 1 illustrating the atent O ice mandrel in forming positionwithin a carton and illustrating the forming head with its pivotalforming jaws in open position.

FIGURE 7 is a section similar to FIGURE 5 but illustrates the jaws intheir closed carton forming positions.

FIGURE 8 is an enlarged vertical section taken along lines 8-8 of FIGURE6.

The carton forming apparatus or turret 10 (FIG. 1)

of the present invention comprises a stationary column 12 which isbolted to a stationary frame 13. A tubular drive column 14 isjourn'alled on the stationary column 12 by bearings 15 and 16. A drivesprocket 17 having a continuously driven chain 18 trained therearoundhas a plurality of equally spaced carriers 19 thereon which carrierssupport vertically extending, open topped cartons C therein.

The drive sprocket 17 and a splash apron 21 are bolted to a drive hub22, which is supported on a vertically adjustable frame 23. The frame 23may be adjusted vertically by means disclosed in the above referred toVadas et al. application so as to raise or lower the carriers 19 therebyadapting the carton forming turret 10 to handle cartons of differentsizes.

The hub 22 is supported'on the adjustable frame 23 for movementtherewith by an annular support 26 which is bolted to the adjustableframe 23 and has the stationary column 12 and tubular column 14projecting upwardly therethrough. A pair of mating thrust bearings 27and 28 are connected to a flange 29 on the lower end of the drive hub22, and to the annular support 26, respectively, thereby permittingrotation of the hub 22 relative to the annular support 26. An S-shapedbracket 31 is bolted to the support 26 and projects over the flange 29to prevent undue separation from occurring between the thrust bearings27 and 28.

A tool supporting hub 32 is bolted to the upper end of the turret drivecolumn 14 and has an upwardly projecting neck 33 rotatably receivedabout a reduced diam eter portion 34 of the stationary column 12. Avertically extending drive post 35 is bolted to the drive hub 22 andprojects upwardly through a suitably bushed drive block 32a that isrigidly secured to the tool supporting hub 32. It will be recognizedthat the drive post 35 transmits rotary motion from the drive hub 22 tothe tool supporting hub 32 yet permits vertical motion of the drive hub22 and associated parts relative to the tool supporting hub 32.

A non-rotatable cam supporting hub 36 is keyed to the reduced diameterportion 34 of the stationary column 12 and has a threaded counter borein its upper end which receives the threaded body 37 of a heightadjustment bushing 38. The bushing 38 includes a small diameter bore 39journalled on a small diameter portion 41 of the stationary column 12,and a large diameter bore 42 journalled on the portion 34 of thestationary column. A handle 43 screwed into the bushing 38 providesmeans for rotating the bushing and thereafter raising or lowering thecam supporting hub 36 to the desired elevation. The cam supporting hub36 is locked at the desired elevation by a threaded collar 44 which isscrewed into the small diameter portion 41 of the stationary column 12.A handle 46 is screwed into the collar 44 to provide means for readilylocking the collar 44 against the bushing 38.

An annular cam 47 having a lower continuous annular track 48 and anupper annular track 49 is bolted to the cam supporting hub 36 and causesvertical reciprocation of a conical anvil 51 and a top forming head 52of each of a plurality of forming head assemblies 53 in timed relationwith the movement of the turret 10.

In the preferred embodiment of the invention the top 3 forming turretcomprises six forming headassemblies 53 which are equally spaced aroundthe turret, and each assembly 53 includes one of the conical anvil 51and one of theforming heads 52. Since all of the assemblies 53 areidentical, only one assembly will be described in detail.

Each forming head assembly 53 (FIGS. 1-4) comprises a C-shaped sub-frame54 which is bolted to the tool supporting hub 32 and slidably receives avertically extending tubular shaft 56 in a upper hub 57 and in a lowerhub 58. A forming head support plate 59 of the forming head 52 is weldedto the lower end of the tubular shaft 56 thereby supporting the forminghead for movement with the shaft. A ve-rtically extending anvilsupporting rod 61 is slidably received in the tubular shaft 56 and hasthe conical anvil 51 secured to its lower end. An abutment collar 62 isclamped against a shoulder 63 adjacent the upper end of the rod 61 by anut 64 screwed on the rod. The collar 62 is disposed in position toengage the upper end of a stop screw 66 which is screwed into the upperhub 57, and is locked in adjusted position by a locknut 67.

In order to vertically reciprocate the shaft 56 and rod 61, and toprevent rotation of the same relative to the C-shaped sub-frame S4,split blocks 68 and 69 are clamped on the tubular shaft 56 and rod 61,respectively. As indicated in FIGURE 5, the split block 69 is clamped toa sleeve- 71 which is slidably received on the outer surface of thetubular shaft 56. A shouldered lug 72 is screwed into the rod 61 andextends through a vertical slot 73 in the tubular shaft 56, through anopening 74 in the sleeve 71, and through an opening in the split block69. A cam follower 76 is journalled on the lug 72 and is held in placeby a nut 77. A cam follower 78 is disposed at substantially 90 relativeto the follower 76 and is journalled on a capscrew 79 screwed into thesplit block 69. Similar cam followers 81 and 82 are journalled oncapscrews secured to the split block 68 and are disposed in verticalalignment with the cam follower 76 and 78, respectively. During rotationof the forming turret 10, the cam follower 81 rides along the upperannular cam track 49, and the cam follower 76 rides along the lowertrack 48 thereby vertically reciprocating the forming head 52 and theanvil 51 in timed relation with the movement of the turret 10. The camfollowers '78 and 82 are received in a vertical cam track 84 formed inthe sub-frame 54 and serve to hold the rod 61 and the tubular shaft 56from rotation relative to the sub-frame.

The conical anvil 51 (FIGS. 6-8) comprises a lower frusto-conciallead-in portion 86 which aids in guiding the anvil into the open topclosure of the carton C. The lead-in portion 86 is connected at acircumferential fulcrurn edge 87 to an upper frusto-conical back-upportion 88 which is secured to the rod 61 as by welding. As indicatedin-FIGURES 6-8, when the conical anvil 51 is in its active position, thecircumferential fulcrum edge 87 is disposed opposite horizontal closurescore lines 89 formed on the rectangular periphery of the carton andconnects the flaps to the body of the carton. Since the anvil iscircular in cross-section, and since the carton is square incross-section, it will be appreciated that there will be littledifiiculty in inserting the anvil 51 into the carton even if the cartonis slightly misaligned, and that the circumferential fulcrum edge 87will engage the carton only at the tangential points of the four walls.

The anvil 51 also includes a threaded shank 92 which has an abutment cam93 screwed thereon and locked in place by a locknut 94. As will be madeapparent hereinafter, the upper surface 96 of the abutment cam 93cooperates with the forming head 52 to cause the inward folding ofopposed flat flaps 97 and 98 only after the opposed trapezoidal flaps 99and 101 (FIG. 8) have been bent inwardly.

The top forming head 52 comprises the above mentioned forming headsupport plate59 Whiclris welded to the tubular shaft 56. Two sets ofspaced fingers 111 and 112 (FIGS. 6-8) having downwardly and outwardly(FIG. 8) flaring lower carton folding surfaces 113 and 114, whichsurfaces flare downwardly and outwardly relative to two perpendicularplanes, are provided for folding each trapezoidal flap 99 and 101inwardly upon downward movement 'of the head 52. Each set of fingers 111and 112 is welded to a support block 116 (FIG. 8) which is rigidlyconnected by cap screws'117 to the plate 59. The upper portion of eachblock 116'is centrally slotted to receive the upper end of a tab bendingfinger 118 having an inwardly bent tab bending portion 119 which upondownward movement of the forming head 52,'engages the associated'tab 121or 122 and bends the tab sharply inward about'its scored fulcrum point123 which rests against the nut 94 as indicated in FIGURE 8. Each tabbending finger 118 is secured to the associated block 116 by cap screws124 which extend through a vertical slot in the finger 118 and arescrewed into the block 116. Thus, downward movement of the head 52causes the fingers 111 and 112 to bend the trapezoidal flaps 99 and 101inwardly, and also causes the fingers 118 to bend the tabs 121 and 122outwardly as indicated in FIG- URE 8.

The forming head 52 also includes a pair of yokes 131 and 132 that arerigidly secured to opposite sides of the plate 59 by capscrews 133. Eachyoke has a centrally disposed slot which receives a tongue 134 (FIG. 1)of a side flap folding jaw 136. Each jaw 136 is pivoted to itsassociated yoke by a pin 138 which is journalled in the yoke and isrigidly secured to the associated tongue 134 as by pinning. A pair ofcompression springs 140 are disposed between each yoke and each jaw 136and are seated in aligned counter bores 144 in the associated yoke andjaw and urge the jaws to their open position illustrated in FIGURE 6.The jaws 136 are not moved inwardly to the flap folding positionillustrated in FIGURE 7 until after the folding head 52 has moveddownwardly a sufficient distance to bend the trapezoidal flaps inwardlyand to enable a pin 145 secured to and projecting inwardly from thetongue 134 of each jaw 136 to engage the upper surface 96 of theabutment cam 93. At this time the jaws 136, which jaws includeconverging flap folding surfaces 146 and sharply beveled fiap crimpingsurfaces 148, swing radially inwardly about the axes of their pivot pins138 thereby forcing the score line 89 of the carton against thecircumferential edge 8-7 of the anvil 51 to crimp the same.

It will be particularly noted that the crimping force is supplied by thearcuate inward movement of the crimping surfaces 148, rather than by adownward sliding movement of the jaws 136 relative to the anvil 51. Ithas been determined that such arcuate inward movement provides asuperior crimping action as compared to the crimping action achieved bydownward movement of the forming head alone.

Although the anvil 51 is circular, it will be appreciated that theadditional structural strength near the corners of the square cartons issufficient to resist inward deflection of the carton body during theforming operation. Thus, it will be apparent that the carton flat flapsare inwardly bent and are crimped at the midpoints of their score lines89, and that these flaps will freely bend about the remaining portionsof the score lines.

During operation of the forming turret 10, the cam tracks 48 and 49first causes the anvil 51 to move from the inactive position illustratedin FIGURE 2 to a position within the carton with its circumferentialedge 87 lying in a common plane with the horizontal closure score lines89 as indicated in FIGURE 3. The forming head 52 is then moved from itsraised position illustrated in FIG- URE 3 downwardly until the two pairsof flap bending fingers 111 and 112 engage the associated trapezoidalflaps 99 and 101 and bend them inwardly. Continued downward movement ofthe forming head 52 causes the pins 145 to engage the upper surface 96of the abutment cam 93 thereby causing the jaws to pivot about theirsupporting pins 138 from the position illustrated in FIG- URE 6 to theposition illustrated in FIGURE 7. The swinging movement of the jaws 136,as contrasted to a downward sliding movement of the jaws relative to thestationary anvil 51, substantially eliminates any tendency of the cartonto slide downwardly upon being contacted by the forming head andaccordingly alleviates any danger of the bending of the flaps to occurat any point other than at the horizontal closure score lines 89. Thefact that the crimping force applied by the pivotal jaws 136 is directedtangentially at the circumferential edge 87 of the anvil 51, rather thanbeing applied as a sliding action downwardly relative to the stationaryanvil 51, also assures a much sharper crimping at the closure score lineof the flat flaps and eliminates all tendencies of the jaws to slideover the outer surfaces of the flat flaps 97 and 98 thereby marring theapperance of these surfaces.

From the foregoing description it will be apparent that the improvedcarton forming apparatus of the present invention includes a crimpinghead having pivotal jaws which remain out of the path of movement of thefiat flaps until after the trapezoidal flaps have been bent inwardlythereby assuring that all cartons will have their top closure flaps bentinwardly in the desired manner, rather than having one or more flapsbent outwardly. The forming turret also includes a crimping head whichincludes pivotal jaws that pivot inwardly against the score lines ofcarton flaps which are resisted by a circular edge of an anvil therebyresulting in sharply crimped flaps of desirable appearance.

While one embodiment of the present invention has been shown anddescribed, it will be understood that various changes and modificationsmay be made without departing from the spirit of the invention or thescope of the appended claims.

The present invention and the manner in which the same is to be usedhaving thus been described, what is claimed as new and desired to beprotected by Letters Patent is:

1. A carton forming apparatus for folding end closure flaps of a cartoninwardly, said flaps being connected to the body of the carton byclosure score lines with two of said flaps having trapezoidal scorelines therein and the other two flaps having flat faces, comprisingmeans for supporting the carton, circular backup means having acircumferential edge insertable within the carton with thecircumferential edge held in position to engage and resist inwardmovement of the closure score lines, an abutment cam rigidly connectedto said resisting means, a reciprocable head supporting plate, opposedflap folding means rigidly secured to said plate and positioned to bemoved by said plate against said trapezoidal flaps to engage and bendthe trapezoidal flaps inwardly, a

pair of opposed flap folding jaws pivotally supported on said plate andhaving flap crimping surfaces, means for reciprocating said supportingplate toward and away from the carton, means normally holding said jawsin pivotal position wherein said crimping surfaces are spaced outwardlyfrom said flaps, and jaw actuating means operatively connected betweensaid jaws and said abutment cam for pivoting said jaws into a closedposition causing said flap crimping surfaces to engage the closure scorelines of the fiat flaps thereby bending the flat flaps inwardly aftersaid opposed flap folding means has first folded both trapezoidal flapsinwardly.

2. An apparatus according to claim 1 wherein said means for normallyholding said jaws spaced outwardly from said flaps are springs, saidsprings being disposed between said jaws and said head.

3. A carton forming apparatus for folding end closure flaps of a cartoninwardly, said flaps being connected to the body of the carton byclosure score lines with two of said flaps having trapezoidal scorelines therein and the other two flaps having flat faces, comprisingmeans for supporting the carton, backup means having a circular edgeinsertable within the carton with the circumferential edge held inposition to engage and resist inward movement of the closure scorelines, an abutment cam rigidly connected to said resisting means, areciprocable head supporting plate, opposed flap folding means rigidlysecured to said plate and positioned to be moved by said plate againstsaid trapezoidal flaps to engage and bend the trapezoidal flapsinwardly, a pair of opposed flap folding jaws pivotally supported onsaid plate and having flap crimping surfaces, means for reciprocatingsaid supporting plate toward and away from the carton, means normallyholding said jaws in pivotal position wherein said crimping surfaces arespaced upwardly from said flaps, and jaw actuating means operativelyconnected between said jaws and said abutment cam for pivoting said jawsinto a closed position causing said flap crimping surfaces to engage theclosure score lines of the flat flap thereby bending the flat flapsinwardly after said opposed flap folding means has first folded bothtrapezoidal flaps inwardly, said jaw actuating means being pins rigidlysecured to said jaws and disposed in position to engage said abutmentcam to pivot said jaws inwardly immediately before said head supportingplate reaches the forming end of its stroke.

References Cited UNITED STATES PATENTS 2,056,330 10/1936 Scott 9336.82,841,942 7/1958 Wills 93-36.8 X 3,153,374 10/1964 Borkmann 9344.13,196,760 7/1965 Terry 9344.1 3,289,553 12/1966 Vadas 93-44 WAYNE A.MORSE, IR., Primary Examiner.

